Technology : .NET/C#
Os targeted : win98 or higher
You need : MS installer, dotnet frame work.
Application Size : 100 KB

Features :
1. Load the list of computer in your intranet.
2. Allow you to manually enter Computers (Buddies).
3. Allow you to rename them with more meaning full names.
4. Multiple messaging.
5. Status reply of each message you sent, so then you can identify the failures.
6. Beautiful Skin. You will like it a lot for sure.